Syrian government warplanes have bombed Kurdish positions in the divided northeastern city of Hasakeh. At least 13 people, including children and women, were killed.

Thursday's was the first of such strikes against a Kurdish-held area of Syria in the country's five-year-old civil war.  It follows heavy clashes on Wednesday between Kurdish fighters who control two-thirds of the city and pro-government militia who control the rest. The two sides share a common enemy - the self-proclaimed Islamic State.

But there have been tensions and sometimes armed clashes between them in Hasakeh. The Kurdish militia People's Protection Units - or YPG - said it would "not be silent" over what it calls an act of flagrant aggression. It is also a key US ally in the fight against ISIL.